Quantitative study on evolution mechanisms of strength and microstructure of cold drawn Cu wire

doi:10.13251/j.issn.0254-6051.2024.10.028

Abstract

Abstract: Three types of Cu wires with different deformation strains were prepared by the cold drawing process. The relationship between the strength, microstructure and strains of the Cu wires was studied. The results show that during the cold drawing process, the strength of the Cu wire shows a trend of rapid increase in the early drawing stage and slow increase in the later drawing stage. Microstructure observations reveal that the grain width of the Cu wire decreases continuously, and the grain orientation gradually rotates from <001> to <111>, forming a high proportion of <111> texture. Additionally, the dislocation density first increases and then decreases with the increase of drawing strains. Further established quantitative relationship between the microstructure and the strength reveals that the grain boundary strengthening and dislocation strengthening are the fundamental reasons for the significant increase in strength of Cu wires during the initial drawing stage. While, the main mechanism for the slow increase in strength of Cu wires in the later stage of drawing is the increase in fine grain strengthening and texture strengthening, as well as the significant decrease in dislocation strengthening.

Key words: pure Cu wire, cold drawing, strength, microstructure

CLC Number:

TG359

Fan Xueyuan, Wang Shuo, Gu Jian, Zhang Zhenjun, Li Dongqing, Liu Zengqian, Hou Jiapeng, Zhang Zhefeng. Quantitative study on evolution mechanisms of strength and microstructure of cold drawn Cu wire[J]. Heat Treatment of Metals, 2024, 49(10): 169-174.

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